<!DOCTYPE html>

<html>
<head>
<style>

div#test {
  zoom: 0.5;
  width: 148px;
  display: block;
}

span {
  background-color: lime;
  float: left;
  width: 70px;
  border: 1.0px solid lime;
}

</style>
<body>

<div id=test>
  <span id=measure>Shouldn't</span>
  <span>wrap</span>
</div>

<div style="clear: both" id=output></div>

<script>
var prop = window.getComputedStyle(document.getElementById("measure")).getPropertyValue("border-width");
document.getElementById("output").innerHTML = "The border width should be 2px, reported as: " + prop;
</script>
</body>
</html>

